The Phenotypic Response Of Duchesnea Indica Connected Ramets Under Heterogeneity Salt Stress And Mediated Regulation

Salt stress is one of the most serious abiotic stress factors.The coastal saline alkali soil is widely distributed and the habitat is bad.With the over exploitation,the area of coastal saline alkali land is expanding,and the productivity of land is declining continuously.The distribution characteristics of salt in saline alkali soil and plant materials are important factors affecting the quality of vegetation cover in coastal saline alkali soil.The salinity distribution of coastal saline alkali soil is usual heterogeneity,affected by the natural factors,such as slope,light,water and so on.Clonal plant form relatively independent ramets by the structure such as stolons and rhizomes,contribute to wide communication and sharing of resources,energy and signal scores between strains of,named physiological integration.Therefore,clonal plant is an ideal material to realize the uniformed distribution of vegetation resources in the heterogeneous site environment.Duchesnea indica is a kind of typical stoloniferous clonal plants with strong resistance,low maintenance cost,has been widely used in the bare ground coverage,such as ground under forests and rocky slope.Study on clonal plant response and adaptation mechanism of Duchesnea indica under heterogeneity of salt stress,has important significance for the application potential of Duchesnea indica.Melatonin is one of most powerful antioxidants,which plays an important role in regulating plant growth and improving plant stress tolerance.Therefore,we analyzed the phenotypic and physiological plasticity response to heterogeneous salt stress in duchesnea indica connected ramets.In this study,the pot experiment was conducted to clone plant Duchesnea indica as materials,studied the mechanism of salt tolerance and melatonin(Melatonin)on the salt tolerance of the control function.The main results are as follows:(1)salt stress inhibited growth of clonal plant Duchesnea indica and affect its physiological metabolism.Under salt stress,the leaf damage rate and leaf dry salt increased Duchesnea death rate increased,dry matter accumulation ability decreased,chlorophyll synthesis was inhibited,the leaves accelerate the loss of water,and cause the cell membranedamage,resulting in the loss of cell membrane permeability,membrane lipid peroxidation reaction and strengthen the accumulation of a large number of hydrogen peroxide.At the same time,salt stress will also increase,stimulate the peroxidase activity of protective enzyme activity of scavenging peroxide,by reducing the damage degree of plant.(2)ramets of physiological integration significantly improve Duchesnea indica have strong adaptive capacity to salt stress habitat heterogeneity.Under salt stress,stress strain and stress can be divided by the ramets sharing water and nutrient resources,a common response to victims in order to reduce the damage by signal,stress of ramets,prolong the survival time of the whole plant,enhance the salt tolerance of plants.(3)exogenous melatonin mediated regulation of phenotypic and physiological heterogeneity of the clones under salt stress response of Duchesnea indica.External melatonin protects Duchesnea under salt stress accumulation and inhibit the degradation of chlorophyll,reduce water loss and protect the cell membrane system,enhance the ability to scavenge peroxides,alleviate the damage caused by salt stress plants.Among them,the concentration of200 mol/L was the most significant.